Surgical management of cardiac pheochromocytoma. Resection versus transplantation

Multimodality Imaging Appearance of Intrapericardial Paragangliomas

Paragangliomas are neuroendocrine tumors of the sympathetic and parasympathetic nervous system that originate from neural crest cells. Less than 1% of paragangliomas are found in the heart, originating from intrinsic cardiac ganglia cells in the posterior wall the atria, atrioventricular groove, and along the root of the great vessels. A 10-year review of our institution's database identified nine patients who had documented intrapericardial paragangliomas. We describe the multimodality imaging appearance of these tumors. The most common findings include embedment and wrapping around the great vessels and atrioventricular groove within the confines of the pericardium, markedly avid heterogeneous enhancement, distinct engorged neovascularization, and in large lesions, central low attenuation areas compatible with hemorrhage, necrosis, or cystic degeneration.

Paraganglioma arising from the liver and abutting the heart

A paraganglioma is a rare extra-adrenal neuroendocrine tumour with a variable clinical presentation. A paraganglioma can arise anywhere along the sympathetic and parasympathetic chains, but it can occasionally emerge from unusual locations such as the liver and the thoracic cavity. We report a rare case of a woman in her 30s who presented to our emergency department with symptoms of chest discomfort, episodic hypertension, tachycardia and diaphoresis. A diagnostic approach including a chest X-ray, an MRI and a positron emission tomography-CT scan showed a large exophytic liver mass protruding into the thoracic cavity. For further characterisation of the mass, a biopsy of the lesion was performed, demonstrating that the tumour is of neuroendocrine origin. This was supported by a urine metanephrine test showing high levels of catecholamine breakdown products. Treatment consisted of a unique multidisciplinary approach involving hepatobiliary and cardiothoracic surgery allowing a safe and complete extermination of the hepatic tumour and its cardiac extension.

A Rare Case of a Right Atrial Paraganglioma in an Individual with the SHDB Mutation

Paragangliomas are extra-adrenal chromaffin cell tumors. A small percentage of these tumors can be found in the thoracic cavity and, when in the heart, are typically in the left atrium. In this case report, we discuss the case of an individual with a history of several paragangliomas with the SHDB mutation who was found to have two cardiac paragangliomas in the right atrium.

Multimodality imaging appearance of intrapericardial paragangliomas

Paragangliomas are neuroendocrine tumours of the sympathetic and parasympathetic nervous systems originating from neural crest cells. Less than 1% of paragangliomas in the heart originate from intrinsic cardiac ganglia cells in the posterior wall of the atria, atrioventricular groove, and along the root of the great vessels. We describe the tumour characteristics, patient demographics, presentation, means of diagnosis, pathology correlation, management, and outcome in 11 patients with intrapericardial paragangliomas. To the authors' knowledge, this is the largest case series reported, with emphasis on multimodality imaging findings.

Cardiac Tumors: Diagnosis, Prognosis, and Treatment

Purpose of Review

Cardiac masses frequently present significant diagnostic and therapeutic clinical challenges and encompass a broad set of lesions that can be either neoplastic or non-neoplastic. We sought to provide an overview of cardiac tumors using a cardiac chamber prevalence approach and providing epidemiology, imaging, histopathology, diagnostic workup, treatment, and prognoses of cardiac tumors.

Recent Findings

Cardiac tumors are rare but remain an important component of cardio-oncology practice. Over the past decade, the advances in imaging techniques have enabled a noninvasive diagnosis in many cases. Indeed, imaging modalities such as cardiac magnetic resonance, computed tomography, and positron emission tomography are important tools for diagnosing and characterizing the lesions. Although an epidemiological and multimodality imaging approach is useful, the definite diagnosis requires histologic examination in challenging scenarios, and histopathological characterization remains the diagnostic gold standard.

Summary

A comprehensive clinical and multimodality imaging evaluation of cardiac tumors is fundamental to obtain a proper differential diagnosis, but histopathology is necessary to reach the final diagnosis and subsequent clinical management.

Resection of Cardiac Pheochromocytoma With Cardiopulmonary Bypass

We report a case of a 21-year-old man with a cardiac pheochromocytoma involving the right atrium and extending to the right ventricular inflow tract, which was diagnosed by somatostatin receptor scintigraphy. For the preoperative evaluation, we chose multiple methods of imaging to accurately describe the anatomic extent and location of the tumor and its surrounding tissues, which showed that no major coronary artery ran through the tumor. The tumor was resected with disease-free margins effectively and safely with the use of cardiopulmonary bypass and with cardiac arrest. The patient remained asymptomatic at the 3-month follow-up.

Single stage hand assisted laparoscopic and trans thoracic excision of multifocal paraaortic and cardiac paragangliomas

A 26-year-old male, with a family history of Paraganglioma Syndrome 4 (PGL4) presented with an 18-month history of paroxysmal headaches, a one-month history of frequent diaphoresis, anxiety attacks and unintentional weight loss of one stone in 2 months. Physical examination and vital parameters were normal. Laboratory studies showed significant elevation of plasma normetanephrines and 3-methoxytyramine while DNA molecular analysis confirmed pathogenic mutation in the SDHB gene and genetic transmission of PGL4. Imaging studies demonstrated a left para-aortic mass in the mid-abdomen and a mediastinal paraganglioma between the root of aorta and origin of the main pulmonary artery, encroaching the right ventricle. After adequate alpha blockade, the patient underwent a combined sequential hand-assisted laparoscopic resection of the abdominal tumour followed by midline sternotomy and resection of the second lesion at the root of the aorta, complicated by the need for emergency cardiopulmonary bypass due to perforation of right ventricular wall.

Cardiac Paraganglioma: Advantages of Cardiovascular Multimodality Imaging

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Cardiac paragangliomas are infrequent tumors.

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The most common location is in the left atrium.

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Cardiovascular morbidity and mortality without treatment are high.

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Different imaging techniques help determine the relation with adjacent structures.

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Multimodal cardiovascular imaging is an essential tool for diagnosis and therapy.

Postpartum Diagnosis of Cardiac Paraganglioma: A Case Report

BACKGROUND

Extra-adrenal pheochromocytomas, or paragangliomas, originate from neural crest chromaffin cells and can be found anywhere along the sympathetic chain from head to toe.

CASE REPORT

A 34-year-old female presented 4 days postpartum with episodes of palpitations, hypertension, and shortness of breath. Two episodes in the emergency department confirmed hypertension and supraventricular tachycardia (SVT). A mediastinal mass was noted during workup for pulmonary embolus and was subsequently diagnosed as a cardiac paraganglioma. Our patient underwent surgical resection and was doing well 3 months postoperatively. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case represents a rare presentation of mediastinal paraganglioma with episodic SVT and hypertension postpartum, diagnosed during workup for pulmonary embolus. Although exceedingly rare, emergency physicians should consider paragangliomas in the differential of pregnant or postpartum women who present with episodic hypertension, palpitations, headache, and sweating.

Resection of Intrathoracic Paraganglioma With and Without Cardiopulmonary Bypass

BACKGROUND

Intrathoracic paragangliomas (PGLs) are rare tumors. Approximately 50% originate from and around cardiac structures.

METHODS

A retrospective review was made of the perioperative course of patients with intrathoracic PGL resection from 2000 through 2015 at Mayo Clinic in Rochester, Minnesota.

RESULTS

Twenty-two patients underwent PGL resection. Sixteen patients (73%) had functioning tumors (11, noradrenergic; 4, mixed noradrenergic and dopaminergic; 1, dopaminergic). Patients with functioning tumors received preoperative adrenergic blockade: 15 (68%), α_1,2-adrenergic receptor antagonist; 4 (18%), α₁-adrenergic receptor antagonists; and 13 (59%) metyrosine. Six patients with nonfunctioning tumors had no adrenergic blockade. Twelve patients had tumor resection without cardiopulmonary bypass-9 for PGL associated with the great vessels, 2 for PGL with pericardial involvement, and 1 for PGL in right atrioventricular groove. Ten patients required cardiopulmonary bypass; for 9, the tumor involved cardiac structures and for 1, it involved ascending aorta and proximal aortic arch. Of these, 1 patient had uncontrollable bleeding and died intraoperatively. Other than this single death, there were no inhospital major cardiac or pulmonary complications. Median follow-up was 8.2 years (range, 2.1 to 17.2). Six patients subsequently had metastatic disease, and of them, 1 died 6 years after the operation.

CONCLUSIONS

In this series, 73% of intrathoracic PGLs were functional and involved noradrenergic, mixed noradrenergic and dopaminergic, or pure dopaminergic secretion. Cardiac and pericardial paraganglioma resection may require cardiopulmonary bypass. Although intraoperative bleeding in most complex cases may be uncontrollable, as for 1 of our patients, those who survived hospital discharge had favorable long-term outcomes.

Right Thoracoabdominal Approach for Retrocardiac Paraganglioma Resection

Paragangliomas are rare extra-adrenal tumors of sympathetic or parasympathetic paraganglia origin; of these, mediastinal paragangliomas are 2% of all cases. We present the case of a 21-year-old woman with uncontrolled arterial hypertension who had a functioning 6.5 × 6.2-cm retrocardiac paraganglioma firmly attached to the pericardium. The patient underwent tumor resection via a right thoracoabdominal incision; this surgical approach enabled adequate exposure for complete resection without institution of cardiopulmonary bypass or need for cardiac reconstruction or autotransplantation. Ten months postoperatively, the patient was doing well and was no longer hypertensive.

Right Atrial Paraganglioma: An Extremely Rare Primary Cardiac Neoplasm Mimicking Myxoma

In this report, we present a case of 35-year-old lady who had presented with atypical chest pain and exertional breathlessness for past six months. Transthoracic and transesophageal echocardiograms showed a well-circumscribed, echo-dense mass in the right atrium, attached to the interatrial septum at the level of atrioventricular junction and in the vicinity of coronary sinus ostium. She underwent successful resection of the cardiac mass. Histopathology revealed paraganglioma, which was reconfirmed by immunohistochemistry study. This represents an extremely rare presentation as primary cardiac tumors are 20-times less common than metastatic tumors and paraganglioma is one of the rarest primary cardiac tumors, accounting for < 1% of all cases.

A completely resected paraganglioma arising from the right atrioventricular groove

We report a case of completely resected right atrioventricular groove paraganglioma. Primary cardiac paragangliomas are extremely rare. Only about 60 cases have been reported in the literature, and most of these tumors originated from the left atrium or the base of the aortic root and pulmonary artery; 5 cases originated from the right atrium. In our patient, the paraganglioma was largely located in the right atrioventricular groove and protruded into the right atrial wall. To our knowledge, there has been no paraganglioma reported in the right atrioventricular groove. We successfully carried out complete tumor resection. Most of these tumors are locally invasive, and complete resection is often difficult.

Surgical excision with left atrial reconstruction of a primary functioning retrocardiac paraganglioma

About 2% of all paragangliomas are located in the chest, and a few have been described to be found in the heart. Primary cardiac paragangliomas are extremely uncommon tumors and surgical experience with this neoplasm is limited. Treatment strategies described in the literature have included simple excision, excision with reconstruction, autotransplantation after excision of the tumor and even orthotopic cardiac transplantation, depending on the extent of disease. A primary retrocardiac paraganglioma catecholamine-productive was identified in an asymptomatic 49–year old female associated to familial pheochromocytoma-paraganglioma syndrome caused by germline mutation of the gen which codifies for the subunit B of succinate dehydrogenase enzyme (SDHB). The neoplasm was surgically excised from the posterior surface of the left atrium via median sternotomy using cardiopulmonary bypass. Direct ligation of feeding vessels of the tumor along with left atrial reinforcement using a pericardial patch was performed. The post-operative course was uneventful, with normalization of catecholamine secretion and no recurrence at three-month follow-up. We review the current literature about this exceptional cardiac tumor, pathophysiological conditions and options for surgical management.

Transthoracic echocardiographic features of cardiac pheochromocytoma: a single-institution experience

BACKGROUND

Cardiac pheochromocytoma is extremely rare. Previous papers usually are reports of a single case. Transthoracic echocardiography (TTE) offers a useful option, but the features of cardiac pheochromocytoma on TTE have not been favorably reported. In this study, the findings of cardiac pheochromocytoma on TTE in nine cases were presented.

METHODS

TTE images (especially two-dimensional ultrasound) of nine patients with cardiac pheochromocytomas were analyzed retrospectively and compared with the findings from surgery.

RESULTS

Among the nine patients with cardiac pheochromocytomas identified in Peking Union Medical College Hospital (PUMCH) clinical and echocardiographic database, TTE identified one cardiac tumor in seven cases (77.8%), two cardiac tumors in one case (11.1%), and a false-negative result in another (11.1%). Cardiac pheochromocytomas were usually located on the base of the heart, near the origin of great arteries. The tumors were usually round or ovoid, ranging from 1.4 cm to 7.7 cm in diameter, with homogeneous and moderate echoes and low activity. They could press or invade surrounding cardiac structures and influence hemodynamics. In this study the majority of cardiac pheochromocytoma seemed marginated and appeared to be encapsulated on TTE. Apical four-chamber view and parasternal short-axis view of the aortic valve were most effective in identifying cardiac pheochromocytomas. The findings on TTE were similar to those from surgical procedures.

CONCLUSION

Cardiac pheochromocytomas presented characteristic TTE appearances in aspect of location, size, texture, and shape of tumors. Understanding of these characteristics on TTE can help correctly recognize this extremely rare disease.

Cardiac pheochromocytoma presenting during pregnancy

A 25-year-old woman presented at 12 weeks gestation, with symptoms and laboratory investigations consistent with pheochromocytoma. Imaging modalities available during pregnancy were limited and MRI scan of the abdomen and the neck failed to localise the tumour. Postpartum imaging, including 131-metaiodobenzylguanidine and octreotide scans, cardiac CT, cardiac MRI and cardiac catheterisation, allowed accurate localisation of the tumour and helped plan for successful surgical removal.

Primary cardiac paraganglioma with dual coronary blood supply presenting with angina chest pain

Primary cardiac paraganglioma (pheochromocytoma) is very rare, constituting only 1% of cardiac tumours. A case of a 44-year-old woman presenting with angina chest pain and a tumour with dual blood supply from both the right and left coronary arteries is reported.

Paragangliomas: etiology, presentation, and management

Paragangliomas are catecholamine-secreting tumors arising from the chromaffin cells of the sympathetic ganglia, and are known as extra-adrenal pheochromocytomas. These tumors commonly present with episodic hypertension, tachycardia, headache, and diaphoresis, and can be either benign or malignant. Diagnosis is made by serum and urine analysis for catecholamines and metanephrines, and confirmed with imaging studies including computed tomography scanning, magnetic resonance imaging, or 123-I metaiodobenzylguanidine imaging. Although the majority of paragangliomas are sporadic, a growing percentage of cases are found to be part of a familial genetic syndrome. Genetic testing should be offered to patients diagnosed with paraganglioma, particularly in patients who are young, have multiple tumors, or have a family history of malignancy. Management of paraganglioma is predicated on surgical resection, and careful perioperative management with alpha- and beta-adrenergic blockade is imperative for optimal outcomes. The majority of these tumors are benign, but for patients with malignant disease, chemotherapy, and radiation therapy may provide modest benefit. Long-term follow-up is essential, as paragangliomas can recur many years after initial diagnosis. Ongoing research into the genetic underpinnings of this tumor may allow for more targeted molecular therapies in the future.

Nonfunctioning benign cardiac pheochromocytoma

PURPOSE

Nonfunctioning benign cardiac pheochromocytoma is one of the rarest tumors and only a few cases have been described before. We present a rare case of nonfunctioning benign cardiac pheochromocytoma and a review of the literature with special emphasis on diagnosis and treatment.

METHODS

Different from the other cardiac pheochromocytomas, its symptoms and signs are so nonspecific that it is easy to make a misdiagnosis or missed diagnosis. One patient with nonfunctioning benign cardiac pheochromocytoma was treated surgically and relevant cases data were collected. Clinical features, diagnosis and treatment of pheochromocytoma were discussed.

RESULTS

The presented case was cured by surgery. The prognosis for patients of benign cardiac pheochromocytomas was excellent, but for those of malignant ones was very poor.

CONCLUSION

Reviewing the few reported cases, most nonfunctioning benign cardiac pheochromocytomas can be cured completely by operation with good prognosis.

Biatrial primary cardiac paraganglioma: a rare finding

The majority of primary cardiac tumors are benign; of these tumors, cardiac paragangliomas are among the rarest. We report a case of biatrial cardiac paraganglioma discovered during workup for palpitations and fatigue. The tumor involved the interatrial septum, with a lobulated portion protruding through the foramen ovale into the right atrium. The tumor was successfully excised, leading to uneventful recovery.

Cardiac Paraganglioma Presenting With Acute Myocardial Infarction and Stroke

We report an unusual presentation of cardiac paraganglioma with acute myocardial infarction and stroke induced by exercise and review the literature regarding this rare cardiac tumor.

Cardiac tumours in children

Cardiac tumours are benign or malignant neoplasms arising primarily in the inner lining, muscle layer, or the surrounding pericardium of the heart. They can be primary or metastatic. Primary cardiac tumours are rare in paediatric practice with a prevalence of 0.0017 to 0.28 in autopsy series. In contrast, the incidence of cardiac tumours during foetal life has been reported to be approximately 0.14%. The vast majority of primary cardiac tumours in children are benign, whilst approximately 10% are malignant. Secondary malignant tumours are 10-20 times more prevalent than primary malignant tumours. Rhabdomyoma is the most common cardiac tumour during foetal life and childhood. It accounts for more than 60% of all primary cardiac tumours. The frequency and type of cardiac tumours in adults differ from those in children with 75% being benign and 25% being malignant. Myxomas are the most common primary tumours in adults constituting 40% of benign tumours. Sarcomas make up 75% of malignant cardiac masses. Echocardiography, Computing Tomography (CT) and Magnetic Resonance Imaging (MRI) of the heart are the main non-invasive diagnostic tools. Cardiac catheterisation is seldom necessary. Tumour biopsy with histological assessment remains the gold standard for confirmation of the diagnosis. Surgical resection of primary cardiac tumours should be considered to relieve symptoms and mechanical obstruction to blood flow. The outcome of surgical resection in symptomatic, non-myxomatous benign cardiac tumours is favourable. Patients with primary cardiac malignancies may benefit from palliative surgery but this approach should not be recommended for patients with metastatic cardiac tumours. Surgery, chemotherapy and radiotherapy may prolong survival. The prognosis for malignant primary cardiac tumours is generally extremely poor.

Cardiac Pheochromocytomas Detected by Tc-99m-Hydrazinonicotinyl-Tyr3-Octreotide (HYNIC-TOC) Scintigraphy

Primary pheochromocytomas of the heart are extremely rare tumors and difficult to diagnose. Iodine labeled metaiodobenzylguanidine (MIBG) is the first choice of the nuclear medicine modality in the evaluation of adrenal pheochromocytoma. However, the sensitivity of MIBG in the diagnosis of extraadrenal pheochromocytoma is less optimal. In this preliminary report, the efficacy of octreotide scintigraphy using Tc-99m labeled hydrazinonicotinyl-Tyr3-octreotide (HYNIC-TOC) in the evaluation of primary cardiac pheochromocytoma was assessed.

Primary cardiac paraganglioma

We report a case of a 29-year-old male, who during workup of hypertension was found to have a malignant primary paraganglioma of the heart. The tumor arose from the site of the aortopulmonary window and right ventricular outflow tract (RVOT) and was removed with the aid of cardiopulmonary bypass. Reconstruction of the RVOT and pulmonary valve was necessary because of involvement by the tumor. The surgical course was uncomplicated, with normalization of catecholamine secretion and blood pressure.

Multiple vertebral metastases from malignant cardiac pheochromocytoma--case report

A 27-year-old male presented with a very rare metastasis to the vertebral body from a cardiac pheochromocytoma manifesting as a pathological fracture of the C-4 vertebral body that occurred while playing golf. The patient was initially treated with hard collar fixation. Gallium scintigraphy demonstrated multiple hot spots in the mediastinum, the frontal bone, the vertebral column, and the rib. Magnetic resonance imaging of the chest delineated a cardiac tumor. The patient underwent biopsies of the cardiac and the frontal bone lesions. The diagnosis was malignant cardiac pheochromocytoma with multiple bone metastases. Initial irradiation of the cardiac and the vertebral lesions was followed by surgical intervention to the cervical spine to prevent aggravation of the kyphotic deformity and spinal cord compression. Preoperative embolization of the feeding arteries was followed by C-4 corpectomy, iliac bone grafting, and anterior titanium plating fixation. The patient was discharged and returned to work. However, 20 months later, he died of a metastatic brain lesion with systemic tumor progression.

[Right atrial pheochromocytoma]

Pheochromocytoma is a catecholamine-producing tumor and a rare cause of hypertension. Most cases are intra-adrenal and intrapericardial pheochromocytomas are extremely uncommon. We report the case of a 46-year-old woman with a 1-year history of hypertension, in which a right atrial pheochromocytoma was detected after a hypertensive crisis. 131I-metaiodobenzylguanidine scintigraphy and magnetic resonance imaging established the diagnosis. The tumor was successfully resected using cardiopulmonary bypass and the right atrium was reconstructed using bovine pericardium.

[Hemodynamic instability and paraplegia after thoracotomy for excision of a cardiac pheochromocytoma]

We report the occurrence of a sustained hypotension (vasoplegia) following thoracic phaeochromocytoma surgery. Diagnosis of spinal cord injury was done by magnetic nuclear resonance (MNR) showing surgical "Horsley wax" inside the vertebral canal and ischaemic signal inside the anterior part of the spine cord. Removal of "Horsley wax" dramatically improved arterial blood pressure but did not correct all neurologic disorders. Haemodynamic disorders related to spinal cord injury are rare after thoracotomy, and may have been enhanced by the haemodynamic instability typically associated with phaeochromocytoma surgery. Early diagnosis has to be done by MNR.

Cardiac phaeochromocytoma presenting with severe hypertension and chest pain

Cardiac phaeochromocytoma is a rare cause of endocrine hypertension. We report a case of a 25-year-old woman, who presented with severe hypertension and intermittent chest pain. The patient denied typical phaeochromocytoma spells of palpitation, headache, and diaphoresis. The 24-hr urinary excretion of norepinephrine was increased sevenfold above the upper limit of normal; however, the excretion of total metanephrines, epinephrine, and dopamine were normal. Computed tomography (CT) scan of the abdomen was normal. An 131I-labelled metaiodobenzylguanidine (MIBG) scan was falsely negative while the patient was taking labetalol. The cardiac phaeochromocytoma was localized with indium-111-pentetreotide scintigraphy and chest magnetic resonance imaging scan. Repeat 123I-MIBG scintigraphy was positive after discontinuing labetalol. The cardiac phaeochromocytoma was located in the right atrial groove, adjacent to the tricuspid valve, and contained multiple feeder arteries from the right coronary artery. After treatment with volume expansion, alpha-methyl-p-tyrosine, and alpha- and beta-adrenergic blockade, surgical resection was performed. While under cardiopulmonary bypass, coronary bypass grafting and tricuspid annuloplasty were performed to facilitate the complete surgical resection of the 4.5-cm tumour. The surgical course was uncomplicated, with complete cure of hypertension and normalization of catecholamine excretion. Post-operative cardiac function, as measured by echocardiogram, was normal. Although cardiac phaeochromocytoma may be highly vascular, invasive and difficult to resect, it can be cured.

Cardiac pheochromocytoma

Primary pheochromocytomas of the heart are extremely uncommon. In this report, we present the case of a patient with primary cardiac pheochromocytoma arising from the interatrial septum. Metaiodobenzylguanidine-scintigraphy was negative and diagnosis was confirmed by a positive octreotide scintiscan. The tumor was removed successfully using cardiopulmonary bypass.

CT and MR imaging of benign primary cardiac neoplasms with echocardiographic correlation

Benign primary cardiac neoplasms are rare but may cause significant morbidity and mortality. However, they are usually treatable and can often be diagnosed with echocardiography, computed tomography (CT), or magnetic resonance (MR) imaging. Myxomas typically arise from the interatrial septum from a narrow base of attachment. Fibroelastomas are easily detected at echocardiography as small, mobile masses attached to valves by a short pedicle. Cardiac fibromas manifest as a large, noncontractile, solid mass in a ventricular wall at echocardiography and as a homogeneous mass with soft-tissue attenuation at CT. They are usually homogeneous and hypointense on T2-weighted MR images and isointense relative to muscle on T1-weighted images. Paragangliomas usually appear as large, echogenic left atrial masses at echocardiography and as circumscribed, heterogeneous masses with low attenuation at CT. These tumors are usually markedly hyperintense on T2-weighted MR images and iso- or hypointense relative to myocardium on T1-weighted images. Cardiac lipomas manifest at CT as homogeneous, low-attenuation masses in a cardiac chamber or in the pericardial space and demonstrate homogeneous increased signal intensity that decreases with fat-saturated sequences at T1-weighted MR imaging. Cardiac lymphangiomas manifest as cystic masses at echocardiography and typically demonstrate increased signal intensity at T1- and T2-weighted MR imaging. Familiarity with these imaging features and with the relative effectiveness of these modalities is essential for prompt diagnosis and effective treatment.

Unusual primary tumors of the heart

Primary tumors of the heart, with the exception of atrial myxomas, occur rarely; tumors metastatic to or directly invasive of the heart are far more common. About 75% of primary tumors are benign, and 75% of these are atrial myxomas. The benign tumors include rhabdomyomas, fibromas, papillary fibroelastomas, hemangiomas, pericardial cysts, lipomas, hamartomas, teratomas, mesotheliomas, and paragangliomas or pheochromocytomas. The last 3 may also be malignant. The malignant tumors consist of various sarcomas: myxosarcoma, liposarcoma, angiosarcoma, fibrosarcoma, leiomyosarcoma, osteosarcoma, synovial sarcoma, rhabdomyosarcoma, undifferentiated sarcoma, reticulum cell sarcoma, neurofibrosarcoma, and malignant fibrous histiocytoma. Cardiac tumors produce a large variety of symptoms through any of 4 mechanisms. Their mass can obstruct intracardiac blood flow or interfere with valve function. Local invasion can lead to arrhythmias or pericardial effusions with tamponade. Bits of tumor can embolize, causing systemic deficits when the tumors are on the left side of the heart. Finally, the tumors may cause systemic or constitutional symptoms. Some tumors, of course, produce no symptoms and become evident as incidental findings. The most useful diagnostic tool is the echocardiogram, which in almost all cases precisely locates the tumor and defines its extent. The echocardiographic appearance may also allow quite accurate prediction of the tumor type and whether it is malignant or benign. Magnetic resonance imaging serves as the next most important test where the density of T1 and T2 images may allow tumor cell type identification. With few exceptions, these tumors require operative excision. Most benign tumors can be resected completely; a few, because of their large size, cannot be, and only tumor debulking may be possible. Heart transplantation should be considered for these patients. Many of the malignant tumors cannot be resected completely, either because of the extent of local spread and invasion or because of the frequent distant metastases. Transplantation may also be an option for those with extensive local disease. The long-term results for resected benign tumors are excellent; the long-term results for sarcomas are very poor, and there are few survivors. For patients with unresectable sarcomas, radiation and chemotherapy may be used, but without great expectation of successful results.